Internal-combustion engine



C. C. MARTIN INTERNAL COMBUSTION ENGINE Filed F eb.20) 1925 5 Sheets-Sheet 1 IN V EN TOR.

QAMWW' .NV.8 ,1927. emmy v c. c. MARTIN INTERNAL COMBUSTION EHGINE Filed Feb. 20. 1925 I 5 hasta-Sheet s INVENTOR.

NM, K9279 c. c. MARTIN INTERNAL COMBUSTION ENGINE Filed F'eb.20. 1925. 5 sheets sheet 4' NW0 8, B92? fi Mgfifi 7 C. c. MARTQN INTERNAL comsusnow ENGINE I N VEN TOR.

4 j 4 IIIIIIIIIIIIIIIIIIIIIIIIIIIIIII/ a W Fatented Nov. 8,1927.

umreos'rarss cent. 0. MAB/rm, or r; MONTANA.

rnrnmtsn-cous'rron inter m Application flled' February a0, 1925. Serial in. 10,574.

The invention relates to improvements in internal combustion engines which have a four stroke cycle of operation; andthe object of the improvement is to obtain a greater 6 efiiciency from' the fuel consumedgthan is obtained by the conventional type of engine.

The mechanism necessary to acquire the advantages of this leverage cycle consists of three mechanical units working so as to control the position and speed of the piston, as well as the turning force on the crank, during the cycle of operation of the engine. The first unit (described in detail under Part A) isa, lever arrangement whereby the speed of the piston and the torque or turning force onthe'crank are made to vary with the pressure of the exploding gas in the cylinder. Since, from the pressure curve for internal combustion engines shown in Figure #5, the. pressure is extremely great at-the beginning of the power stroke and adually decreases to the end of this stroke,

.11; is possible, by this arrangement, to distribute the torque or'turning force onthe crank more evenly over a larger arc of the crank circle thanit is 1n the ordinary engine,

The second unit (described in detailunder Part B) is fora scavenger pur ose and is to completely exhaust the c lin 0 power "Stroke. Since near y one-fifth of the volume of a.cylinder,in an engine operating at 65 pounds gauge compression at sea level, is used on the compression cavity, practi cally twenty percent of the explosive mixture consists of burned gases not excluded during the previous cycle of operation. By this mechanical arrangement nearly all the products of combustion are exhausted from I the cylinder after each explosion," and the efliciency of the explosive mixture is greatly increased. The third unit, (described in detail under 'Part C) is for the purpose of holding the piston at its highest position on "compression until the crank has passed er after the proved engine, and

Figure 10 is another sectional view of my through dead center and, in this way, elimi-- Figure 2 is a diagrammatic illustration of the engine at the beginning of the compression stroke, Figure 3'is a diagrammatic illustration of the engine at the beginning of the power stroke,

Figure 3 is a diagrammatic illustration of the engine at the beginning of the power stroke just beyond dead center,

Figure 4 is a diagrammatic illustration of the engine at the beginning of the exhaust stroke,

Figure 5 1s a graph of the pressure curve I for the common it-cycle engine, Figure 6 is a plan view of the adjustable arm Figure 6 is a side view of the adjustable arm Figure 7 is a plan view of the secondary connecting rod,

Figure 7 is a side view of the secondary connecting rod,

' Figure 8 is a side view of the race-way a-rm v arm I -Figure 8 is a section along the line '-A' of 8, Figure 9' 1s a sectional view of my imimproved engine. a

The Figures #1, '2, 3, 3 and 4 are crosssectional-line drawings in a plane through the axis of the cylinder and perpendicular to the axis of the crank shaft. In

these drawings ABSD re resents a section through the cylinder. F is equal to the radius of the crank. The arrow A indi-- cates the direction of rotation of the crank. IH represents the amount of-eecentricity of an eccentric which rotates in the same direction as the crank shaft with a fpeed ratio of 1 :2 to the crank shaft. In the ollowing discussion this eccentric is considered as being on the cam shaft. HJ is'a raceway arm or -'-slider arm in which the slider KL movesas Figure 8 is a plan view of the race-way HJ reciprocates about H as a center. The po-' sition of the point J controls the position of the piston through the primary connecting rod MN. The ad uSting arm OR is stationary at 0 but allowed to reciprocate about. O as an axis. OR .determinesthe position of the slider KL in the raceway arm HJ. TF is a secondary connecting rod from the slider to the crank. v

Figure #1 shows the position of the working parts at the end of the exhaust and beg' of the intake strokes. The point E is th 'ghest position of the piston during the exhaust stroke. As the crank moves in the directionof the arrow A the connectin rod'TF pulls the adjusting and OR aroun O as an axis. the point B. moves around 0 it forces the slider KL alon the slider arm HJ and pulls HJ around as an axis. J pulls 'down the piston, admitting the explosive gas into the cylinder.

Figure #2 shows the position'of the working parts at the end ,of the intake and begmnm g of the compression strokes. The

oint is the lowest osition of the piston ur' the intake stro e. During the time that t e crank has assed over the arc necessary for the inta e-istroke, the point of greatest eccentricity H, on the eccentric IH,

as moved over half this are; sinceH is on the cam shaft and geared to the crank shaft with a speed ratio of 1:2. As the point F follows around the crank circle it forces up the secondary connecting rod TF and moves R around 0 as an axis. As R moves around 0 the slider KL moves alon the slider arm HJ at the same time HJ is ing forced up by KL raises HJ and compresses the gas in the cylinder.

Figure #3 shows the position of the workingparts at the end of the compression and beginning of the power strokes. The int C shows the highest position of the piston during the compression stroke. During the time the crank has passed over the arc necessary for the compression of the gas the excentric HI has moved through half the arc and is now at the point H in Figure #3. As the piston is forced down'by t e explosion, the raceway arm HJ is forced around H as an, axis. As HJ swings around H, the

slider KL is forced down against TF and results-in a turn' force on the crank. As TF moves down, t e slider KL is forced out along the slider arm HJ b the adjusting arm OR which moves aroun O as an axis.

Figure #4 shows the position of the'workparts at the end of the power and beginning of the exhaust strokes. The point shows the lowest position of the piston during the power stroke. As the exhaust rt 0 us the point F. forces TF on KL and 'fts t e raceway arm HJ. HJ raises the piston to the point E and completely exhausts the cylinder of those products of combustionformed during the power stroke.

Although in this specification IH ,is con- 'sidered as the amount of eccentricity of an eccentric on the cam shaft, this eccentric may be on a separate eccentric unit; 'but, since both the cam shaft operating the valves and of construction.

7 Part A. I a

In this part of the specification the-action of the eccentric IH is disregarded, and the point R is considered as being at T or the adjusting arm OR is. considered-connected -to the secondary connecting rod at T. The

pressure curve for a.common four stroke cycle engine, shown in Figure #5, shows the pressure to be at a maximum at the beginning of the power stroke and to gradually decrease to the end of this stroke. Because of the great pressure the piston may .be allowed to move at a high rate of speed at the beginning of the power stroke without I d of the .en-

relatively decreasing the s gine. in Figure #3, at t e beginn' of the power stroke, 1f the-ratio of H-- to H-KL is as 2 is to 1, the pressure at T will be approximately twice the pressure at N, and the force exerted at F will be a proximately twice the force exerted, on t e 'crankof a common type of engine at this position of operation. The piston, during the first part of the wer stroke, will travel twice as fast as it oes in.the ordinary englue and the pressure will be utilized nearly as it is formed. This action willgive the 'same effect on the operationof the en ine as the use of tellurium or lead compoun s to retard the-formation of high pressures at the beginning of the power stroke. The

greater speed of the piston will give a release tothe pressure and 'lessen the tendency to develop knocks. As the piston is forced down by the explosion the slider will move out in the raceway arm HJ, and decrease the I leverage at F as the pressure in the cylinder decreases and the torque component of the force at .F increases tending to equalize. the turning force on the crank over a large arc, and to keep the speed of the piston nearly llll constant durin the first hundred degrees of p the power stro e. During the power stroke the crank will pass through approximately g in 215 degrees of arc althou t e ordinary engine the power is distributed over only 180 degrees of are. By this mechanism a greater amount of the energy in the explosive mixture will be transformed into mechanical power by distributing the torque more evenly over a larger arc of the crank circle. ThlS engine will not consume as much fuel as the conventional type of engine with cylinders of equal proportions, because the piston stroke is greater than'the crank stroke. During the intake stroke the intake ports may be allowed to close before the piston has reached its lowest position,

and, in this manner, limit the volume of. gas

' consumed during each cycle of operation.

This will result in a saving of fuel by allowing a more complete expansion of the exploding gas, since the volume of the cylindercavity will be greater at the time or opening pletely exhausting the cylinder after the power stroke and still leave suflicicntspace for a compression cavity during the compression stroke. It consists of an eccentric on the cam shaft which rotates, in thesame direction as thecrank shaft, and with a.

- speed ratio of 1:2 to the crank shaft. This eccentric controls the position of the bearing H, or the bearing, about which the raceway arm HJ reciprocates. Atthe end of the -exhaust and beginning of the intake strokes,

the position of greatest eccentricity will be at Hin Figure #1. It will be close to, and lower than, the surface ,Th s will cause the reciprocating end of the raceway arm to be at its highest position during the cycle.

of operation, and the piston, at that time, will completely exhaust the cylinder before beginning the'intake stroke. At the end of the compression and beginning ofthe power strokes the point of greatest eccentricity; on

tion of By the time the piston starts to drop, or at the time of ignition, the crank will be off dead center and there will be a torque component of the force exerted at F.

In this spehification I have considered the me hanism necessary for the Martin leverage cyc e as three units described under Parts A, B, and G; not only because I could makemy explanation clearer in this manner, but also to show that the first unit, described in Part A, can be incorporated into an engine,

. and give it the advantages of the first unit without the use of the units described under Parts B and C. The first and second units unay be used in an engine and gainthe advantages described under Parts A and B, or

.alltliree units may be assembled in the same engine and acquire the summation of the advantages of each. Q

Figures #6, 7, 8, 9, and 10 are mechanical drawings or the parts as they may be constructed in the practical application of my invention. The primary connecting, rod, MN in Figures #9 and 10, may be a straight connecting rod with a wrist pin clamp at each end. The raceway arm or slider arm,-

shown in Figure #8, and shown as HJ in Figures #9 and 10, may be made with a wrist pin bearing at its reciprocating end J, and a larger babbitted bearing at H, its connection with the eccentric.

Figure #8 to give 'a' maximum sliding surthe cam shaft will ha oved-from H in face. The slider, KL in Figures #9 and Figure #1 to H in Figure #3. 'Ttwillmefw t be made to fit the raceway of the farther from KL than it was inFigure 1,

Part 0'.

The action of the piston with regard to the position of the crank- F, caused by the positions of the points R and H, is considered as the third part of the invention. It enters advantageousl into the scheme only at the beginning-of t e power stroke. If the bearing at R was at T as soon as the crank pin F ad center lhefl on would start to drop; but since the connection is at B, when F moves ofi' deadcenter it forces the secondary connecting rod TF to pivot. about R as an axis. This will move T nearer to the oint H, as in Figure #3, and move the sli er KL towards the eccentric 11-1. The hearing at J will lift'slightly, and tend to raise or hold the piston in its'highest ositionron compression stroke, until the li actio n of KL is overcome by the lowering acraceway arm.

The secondary connecting rod, TF in Figures structed as shown in igure #7, with a babbitted bearing at its connection with the crank F;'and a wrist pin bearing at T, its

connection with the slider. At the connection of the secondary connecting rod with 9 and 10, may be con r The raceway .ofthls part may be constructed as shown in the adjusting arm, R in Figures #9 and 10, a

may be protruding stud bearings, but in a construction which magnified the effect produced by the position of this bearing, a

wrist pin bearing may be used. The adjusting arm, OR in Figures 9 and 10 and shown in Figure #6, may bent so as to clear the eccentric bearing of the raceway arm at the end of the exhaust stroke. Figure #9 shows the position of the workin parts of a practical construction at the en of the intake stroke. Figure #10 shows the position of the working parts of the same construction at the end of the exhaust stroke. These two positions are shown because they illustrate the highest and lowest positions of the piston during the cycle of operation. 'What I claim as myinvention is 1. A device of the type described comprising a cylinder, a piston disposed in said cylinder, a crank shaft, and means for connecting said piston .to said crank shaft, said means including a primary connecting rod secured at one end to said piston, a sec-.

ondary connecting rod secured at one end v to said crank shaft, and means operatively connected to the otherends of said con necting rods for holding said primary con- "end to sai crank shaft, and means connect-- ing the other ends of said connecting rods whereby said piston and said primary connecting rod are held against movement when said piston is in the outermost position and permitting movement of said secondary connecting rod, said means including a slider arm and a slider adapted to move. with respect to said slider arm.

3. A device of the type described com prising a cylinder, a piston disposed in said cylinder, a crank shaft, a primary connecting rod secured at one end to said cylinder,

- a slider arm pivotally secured at one end to 'the other end of said primary connecting rod and having grooves disposed longitudinally therein, an eccentric, the other end of said slider arm operatively connected to said eccentric, a slider, tongues integral with said slider and receivable within the grooves in said slider arm, and a secondary con necting rod pivotally mounted at .one end upon said slider and at the other end upon said crank .shaft, said slider arm being adapted to hold said primary connectingrod and said piston in the outermost position and permitting said slider to move withrespect to said-slider arm during the ,rnovement of said crank shaft'past dead center;

4. A device of the type described comprising a cylinder, a piston disposed in said cylinder, a crank shaft, a primary connecting rod secured: at one end to said cylinder, a slider arm pivotally secured at one end to the other end of said primary connecting rod and having grooves disposed longitudinally therein, an eccentric, the other end of said slider arm operatively connectedto said eccentric, a slider, tongues integral with said slider and receivable within the grooves in said slider arm, a secondary connecting I rod pivotally mounted at one end upon sai slider and at,the other end upon said crank shaft, said slider arm being adapted to hold said primary connecting rod and said piston in the outermost position and permitting said slider to. move with respect to said'slider arm during the movement 'of said crank shaft. past dead center, and means operatively connected to said secondary connect ing rod for guiding said secondary con necting rod and said slider in their move ment.

In testimony whereof I-aflix my signature.

CARL C. MARTIN. 

